Energy Performance Certificates (EPCs) or Building Energy Ratings (BERs) in Ireland, are mandated for buildings constructed, sold, or leased across the European Union (EU). They are the foremost source of information on energy use in EU building stocks which informs climate policy. However, the use of EPC data to predict energy use and the impact of policy interventions is questionable. Inherent in all EPC methodologies are trade-offs between reproducibility, accuracy, assessor expertise and costs. Since input data is often based on worst-case default and standardised operating conditions; the results outputted by EPC methodologies can only offer an estimation of the actual building energy consumption. Indeed, there can be a major gap between theoretical and actual measured energy consumed in occupied buildings. PREDICT addresses this gap through the creation of an adaptive in-use factor (IUF) tool to predict occupied building energy use.